The Washington Post

Promises of greater longevity via the many vitamins, pills, hormones, diets and exercise regimens currently on the market aren't likely to pan out in the 21st century, according to some scientific investigators presenting their thoughts at the recent American Association for the Advancement of Science meeting in San Francisco.

A new study forecasts that even the countries that have made the greatest lifespan improvements to date - France and Japan - will not reach a life expectancy at birth of 100 years until the 22nd century. The 100-year benchmark won't be hit in the United States until the 26th century. S. Jay Olshansky, of the University of Illinois at Chicago, and colleagues suggest that a life expectancy of 85 years for both sexes combined is a more practical target, with France and Japan projected to reach that goal in about 30 years, and the United States likely to join them around 2180.

"A life expectancy at birth of 100 years, if it ever occurs, is unlikely to arise until well past the time when everyone alive today has already died," said Olshansky. "The rise in life expectancy in the future will be measured in days, weeks and months - not in decades, as some proponents of extreme longevity predict."

Life expectancy shot up dramatically during the past century, rising by about three decades in industrialized countries thanks in large part to falling death rates in the young from infectious diseases. Today life expectancy is about 79 years for American women and 72 years for men. But the U.S. mortality advantage over other industrialized countries is disappearing, said Olshansky. From 1985 to 1995 U.S. death rates showed only a 0.4 percent average annual decline and even increased among males 27 to 45 years old and 89 years and above. This compares with an annual overall drop of 1.5 percent in France and 1.2 percent in Japan.

The reasons for the differences - genetic, lifestyle or health care - are not clear, said Olshansky. The rising death rate in younger American men was linked in part to HIV.

Olshansky said the only hope for another quantum leap in future life expectancy is if "researchers can discover how to modify the aging process and make such a discovery widely available to the entire population," a prospect he considers highly unlikely.

Leonard Hayflick, of the University of California at San Francisco, shared Olshansky's pessimism. "No evidence supports the many outrageous claims for an extraordinary increase in life expectancy," said Hayflick. Even if medical science were able to cure all of the top killers, such as heart disease, cancer and stroke, Hayflick said, only about 15 years would be added to life expectancy.

University of Southern Denmark researcher Kaare Christensen, 41, was more optimistic. "There is no evidence that human life span is approaching a limit," he said, citing "a remarkable decline in the mortality for the oldest." He noted that the number of centenarians is doubling every 10 years and longevity records are repeatedly being broken.

The researchers agreed that the size of the elderly population will continue to grow as baby boomers age and that the emphasis should be on improving quality of life. Olshansky, age 47, suggested calculating the "health expectancy" of a population, or the amount of time spent in good health.

Hayflick, at age 72, admitted he would not mind making it to "age 100 with full use of physical and mental capacity - and dropping dead at the stroke of midnight."